Container

ABSTRACT

A container has a rectangular base and two opposite end faces each formed by a rigid frame surrounding a solid wall. Longitudinal members parallel to the longitudinal axis of the base plate connect the upper corners of the end frames. A flexible sheet metal membrane is welded around its entire periphery to the longitudinal edges of the base plate and to the edges of the end frame distinct from the base plate. The membrane passes over the longitudinal members and bears on them without being fixed to them. The external outline of the longitudinal members is shaped in the form of two clothoid portions symmetrical relative to the bisector of the angle formed by the faces defined by the longitudinal members, so that the membrane can slide over them easily without undergoing a sharp bend.

[ 1 Aug. 1,1972

7 CONTAINER [72] Inventor: Remy Dousset, Lyon, France [73] Assignee:Societe Nouvelle Des Ateliers De Venissieux, Venissieux, France Filed:June 1, 1971 Appl.No.: 148,443

[52] US. Cl. ..220/4 R, 220/DIG. 25 [51] Int. Cl. ..B65d 7/00 [58] Fieldof Search ..220/1 B, 4 R, DIG. 25

[56] References Cited UNITED STATES PATENTS 799,755 9/ 1905 Powell et a1..220/4 R 1,276,031 8/1918 Casper ..220/4 R X 1,394,936 10/ 1921 Pratt..220/4 R 2,501,980 3/1950 Wolfe ..220/4 R FOREIGN PATENTS ORAPPLICATIONS 1,173,744 3/1959 France ..220/4 R 1,491,264 7/1967 France..220/4 R 751,949 7/ 1956 Great Britain ..220/4 R 90,489 2/1959Netherlands ..220/4R Primary Examiner-M. Henson Wood, Jr. AssistantExaminer-Edwin D. Grant Attorney-Cameron, Kerkam & Sutton [5 7] ABSTRACTA container has a rectangular base and two opposite end faces eachformed by a rigid frame surrounding a solid wall. Longitudinal membersparallel to the longitudinal axis of the base plate connect the uppercorners of the end frames. A flexible sheet metal membrane is weldedaround its entire periphery to the longitudinal edges ofthe base plateand to the edges of the end frame distinct from the base plate. Themembrane passes over the longitudinal members and bears on them withoutbeing fixed to them. The external outline of the longitudinal members isshaped in the form of two clothoid portions symmetrical relative to thebisector of the angle formed by the faces defined by the longitudinalmembers, so that the membrane can slide over them easily withoutundergoing a sharp bend.

3 Claims, 4 Drawing Figures PATENTEDAUB 1 I972 SHEET 2 0F 2 FIG -.4

l CONTAINER The invention relates to a container, more particularly, forexample, a container for transport by sea. All containers and, moregenerally, all rigid packs for transporting material either in bulk orwhen contained in inner packs, are usually formed by an at leastapproximately parallelepipedal envelope.

During transport and handling, as a result of acceleration, decelerationor changes of direction, the contents of the container may exert on itsfaces stresses much greater than the ordinary stresses exerted when thecontainer is at rest on a horizontal plane. For example, the lateralfaces of marine containers are required, if the ship rolls, to withstanda force of approximately 0.6 times the weight of the load enclosed inthe container.

In conventional containers, each face is constructed so that it canwithstand alone the stresses to which it is subjected'during transportand handling. The faces are generally formed of a frame surrounding awall, which may be a fairly thick sheet of fiber-reinforced plywood, asandwich panel, corrugated iron or ribbed sheet metal. All these paneltypes are used to form walls because their inherent rigidity enablesthem to withstand the load, but they are heavy and expensive.

Container walls have also been formed of flat sheets of metalfunctioning as membranes. These are lighter and more compact than thewall panels mentioned above, so that the effective capacity of thecontainer can be increased. The sheet-metal membrane does not, however,have the strength to resist the internal pressures, all of which aretransmitted to the frame surrounding the membrane. The smaller thedeformation, the more the pressures transmitted are amplified. The frameis therefore highly stressed, so that its construction must be heavy andexpensive.

The invention makes it possible to provide a thinwalled containercapable of withstanding the stresses on its lateral faces withoutexcessive reinforcement of its framework, and provides a containercomprising a rectangular base plate, two opposite end faces each formedby a frame surrounding a solid wall, elements parallel to thelongitudinal axis of the base plate connecting the end frames, and acontinuous membrane fixed around its entire periphery to thelongitudinal edges of the base plate and to those edges of the endframes distinct from the base plate, the membrane bearing on, but notbeing fixed to the said elements.

A container according tov the invention will now be described, by way ofexample, with reference to the accompanying drawings.

FIG. 1 is a simplified end view of the container showing how it isdeformed by a force applied to a lateral face; 1

forming three faces of the container, showing the dis- As FIGS. 1 and 2show, the container has a base plate 1 and two lateral faces 2, 3. Eachof these lateral faces 2, 3 consists chiefly of a rigid frame formed byvertical end uprights 4 or 5 and upper cross-members 6 or 7respectively. The other two lateral faces and the roof of the containerare formed by a single metal sheet 10 bent around upper longitudinalmembers 11, 12 and welded around its entire periphery to lowerlongitudinal members 13, 14 and to the vertical uprights 4, 5 and uppercross-members 6, 7.

When the load inside the container is subjected to transverseacceleration due, for example, to rolling, it exerts a force F (FIG. 1)on the center of one of the lateral faces. This force causes the metalsheet to bulge out and stretch.

In the case of a conventional container, in which the lateral face is asheet held in a strong frame which defines this face, this force F isbalanced by all the tensions T arising in the sheet. If the face issymmetrical it is possible to write, as a first approximation,

a being the angle formed by the deformed sheet with the plane of thewall'before deformation. With a sheet of ordinary steel the stretch issmall, and it is possible to assume that Sin a=-a, whence T=( F/2 a).

By contrast, in. the case of the novel container described above, theinfluence of the force F extends to all the three faces covered by thecontinuous membrane. An identical force therefore causes approximatelythree times as much stretch in the membrane as is observed in aconventional container. The angle a also increases, thoughnotproportionally, and becomes a. The tensions T arising in the membranemay be expressed as T =(F/2 a), the angle a being appreciably greaterthan a, so that the stresses in the membrane of the container aredistinctly smaller than those in a conventional container. Figure 3,which shows the sheet 10 expanded flat, indicates, at leastqualitatively, the distribution of the stresses applied by the membraneto the fittings supporting it.'This distribution does not allow for thereaction from the upper longitudinal members B B and C C since except atthe ends of these members the deformation of the whole manifests itselfonly by sliding of the sheet over its longitudinal members. The onlyresult is compressive stressing of these upper longitudinal members,which may be reinforced either with uprights or cross-members or withsuitably sited struts to prevent them from bending excessively.

It is therefore important that the sheet 10 should be able to slidefreely over the upper longitudinal members B B and C C. For this purposethe outline of these longitudinal members is curved. Also, to protectthe sheet from alternating deformation as it repeatedly slides over thelongitudinal members, a preferred embodiment of the longitudinal membershas an external outline whose radius of curvature varies progressivelybetween a very large radius atthe point where it joins the flat surfacesand a small radius in its center. The curve representingthe externaloutline of the longitudinal member is therefore composed of two clothoidportions symmetrical relative to the bisector of the angle formed by thetwo faces.

An approximate indication of such a curve is given in FIG. 4, in whichthe central portion 1 of the outline is a circular arc of center theportions 2 and 2' on each side of this central portion are circular arcsof centers 0 and 0' respectively, the arcs 3 and 3 are circular arcs ofcenters 0 0' and so on.

At any point of contact between the sheet and the longitudinal member,therefore, the maximum amplitude of the sliding motion of the sheet onthe longitudinal member will not cause the radius of curvature to varymore than the sheet can stand without undergoing permanent deformation.

It may be noted, also, that the shape of this external outline of thelongitudinal member makes it closer to a right-angle than to a circulararc, so that the volume lost for given overall dimensions is reduced.

Obviously, the invention is not strictly limited to the singleembodiment given by way of example, but also covers other embodimentswhich differ only in detail. For example, the metal sheet forming themembrane, which is welded around its entire periphery, might be replacedwith a membrane, not necessarily metal, which is fixed around itsperiphery not by welding but by any other known means, for example bymeans of clamps, hooks or other fastenings, lacing or adhesive. Anon-welded construction may make loading of the container faster.

I claim:

1. A container comprising a rectangular base plate, two opposite endfaces each comprising a frame and a solid wall surrounded by the frame,elements parallel to the longitudinal axis of the base plate connectingsaid end frames, and a continuous membrane secured around its entireperiphery to the longitudinal edges of the base plate and to the edgesof said end frames distinct from said base plate, said membrane bearingon, but not being fixed to, said elements.

2. A container according to claim 1 wherein said membrane comprises asingle metal sheet welded around its entire periphery to thelongitudinal edges of said base plate and to the edges of said endframes distinct from said base plate.

3. A container according to claim 1 wherein the external outline of saidelements has the shape of two clothoid portions symmetrical relative tothe bisector of the angle formed by the faces defined by said elements.

(5/69) TED STATES PATENT @FMCE Patent No. 3 680, 728 Dated August 1 1972Inventor(s) Remy Dousset It is certified that error appears in theabove-identified patent and that said Letters Patent are herebycorrected as shown below:

FD [30] Foreign Priority Application June 17, 1970 W France ..7022237,is omitted.

Signed and sealed this 30th day of January 1973..

(SEAL) Attest:

EDWARD MFLETCHER,JR. ROBERT GOTTSCHALK Attesting Officer Commissioner ofPatents

1. A container comprising a rectangular base plate, two opposite endfaces each comprising a frame and a solid wall surrounded by the frame,elements parallel to the longitudinal axis of the base plate connectingsaid end frames, and a continuous membrane secured around its entireperiphery to the longitudinal edges of the base plate and to the edgesof said end frames distinct from said base plate, said membrane bearingon, but not being fixed to, said elements.
 2. A container according toclaim 1 wherein said membrane comprises a single metal sheet weldedaround its entire periphery to the longitudinal edges of said base plateand to the edges of said end frames distinct from said base plate.
 3. Acontainer according to claim 1 wherein the external outline of saidelements has the shape of two clothoid portions symmetrical relative tothe bisector of the angle formed by the faces defined by said elements.